diff --git a/nix/configuration/configuration.nix b/nix/configuration/configuration.nix
index 0459230..08f6422 100644
--- a/nix/configuration/configuration.nix
+++ b/nix/configuration/configuration.nix
@@ -260,6 +260,7 @@ in
           );
         })
         (disableTests "onetbb") # oneTBB tests hang forever on machines with a single core (like my build virtual machine) https://github.com/uxlfoundation/oneTBB/issues/1557
+        (disableTests "aws-c-common") # aws-c-common tests time out on my build virtual machine but run fine on my laptop.
 
         # Works but probably sets python2's scipy to be python3:
         #
diff --git a/nix/configuration/flake.lock b/nix/configuration/flake.lock
index 4ccc6e9..f73c54d 100644
--- a/nix/configuration/flake.lock
+++ b/nix/configuration/flake.lock
@@ -162,6 +162,27 @@
         "type": "github"
       }
     },
+    "nix_builder": {
+      "inputs": {
+        "nixpkgs": [
+          "nixpkgs"
+        ],
+        "rust-overlay": "rust-overlay_2"
+      },
+      "locked": {
+        "lastModified": 1783278211,
+        "narHash": "sha256-/1u+MIQIge+cNPukQoK4Jp8nLuFZRbx4U+MyyxG0RpM=",
+        "ref": "refs/heads/main",
+        "rev": "9281ba7e10d362d4edb489d0df0e78936dfe7b58",
+        "revCount": 32,
+        "type": "git",
+        "url": "https://code.fizz.buzz/talexander/nix_builder.git"
+      },
+      "original": {
+        "type": "git",
+        "url": "https://code.fizz.buzz/talexander/nix_builder.git"
+      }
+    },
     "nixpkgs": {
       "locked": {
         "lastModified": 1780749050,
@@ -242,6 +263,7 @@
         "disko": "disko",
         "impermanence": "impermanence",
         "lanzaboote": "lanzaboote",
+        "nix_builder": "nix_builder",
         "nixpkgs": "nixpkgs",
         "nixpkgs-google": "nixpkgs-google"
       }
@@ -266,6 +288,27 @@
         "repo": "rust-overlay",
         "type": "github"
       }
+    },
+    "rust-overlay_2": {
+      "inputs": {
+        "nixpkgs": [
+          "nix_builder",
+          "nixpkgs"
+        ]
+      },
+      "locked": {
+        "lastModified": 1779506148,
+        "narHash": "sha256-OffE5yuMrSW71zIJNLvtl9MCO6WTAHEjlFPUCvkd/QM=",
+        "owner": "oxalica",
+        "repo": "rust-overlay",
+        "rev": "d9973e2ab49747fada06ebbe26cda27eb0220cf1",
+        "type": "github"
+      },
+      "original": {
+        "owner": "oxalica",
+        "repo": "rust-overlay",
+        "type": "github"
+      }
     }
   },
   "root": "root",
diff --git a/nix/configuration/flake.nix b/nix/configuration/flake.nix
index 0944029..63e4c02 100644
--- a/nix/configuration/flake.nix
+++ b/nix/configuration/flake.nix
@@ -29,6 +29,10 @@
       url = "github:nix-community/disko";
       inputs.nixpkgs.follows = "nixpkgs";
     };
+    nix_builder = {
+      url = "git+https://code.fizz.buzz/talexander/nix_builder.git";
+      inputs.nixpkgs.follows = "nixpkgs";
+    };
   };
 
   outputs =
@@ -39,6 +43,7 @@
       disko,
       impermanence,
       lanzaboote,
+      nix_builder,
       ...
     }:
     let
@@ -70,7 +75,7 @@
         hostname: nodeConfig: format:
         nixpkgs.lib.nixosSystem {
           specialArgs = {
-            inherit self;
+            inherit self nix_builder;
 
             this_nixos_config = self.nixosConfigurations."${hostname}";
 
diff --git a/nix/configuration/roles/hydra/default.nix b/nix/configuration/roles/hydra/default.nix
index 6b0803a..07e3bdd 100644
--- a/nix/configuration/roles/hydra/default.nix
+++ b/nix/configuration/roles/hydra/default.nix
@@ -2,56 +2,10 @@
   config,
   lib,
   pkgs,
+  nix_builder,
   ...
 }:
 
-let
-  # patchScriptBin =
-  #   {
-  #     filename,
-  #     contents,
-  #     path ? [ ],
-  #   }:
-  #   ((pkgs.writeScriptBin filename contents).overrideAttrs (old: {
-  #     buildInputs = [ pkgs.makeWrapper ];
-  #     buildCommand = "${old.buildCommand}\n patchShebangs $out\nwrapProgram $out/bin/${filename} --prefix PATH : ${lib.makeBinPath path}";
-  #   }));
-  nix_builder = pkgs.rustPlatform.buildRustPackage rec {
-    pname = "nix_builder";
-    version = "0.0.0";
-
-    src = pkgs.fetchgit {
-      url = "https://code.fizz.buzz/talexander/nix_builder.git";
-      # tag = version;
-      rev = "606832f505a1ccc9702cd12c236c3188f9282e82";
-      hash = "sha256-WHvnkCIPDBw0BnrQMnBpmwmYuhlxR4FfkoNWw2DY6XE=";
-      leaveDotGit = false;
-    };
-
-    cargoLock = {
-      lockFile = "${src}/Cargo.lock";
-    };
-
-    meta = with lib; {
-      description = "A builder of nix configs for a build server.";
-      homepage = "https://code.fizz.buzz/talexander/nix_builder";
-      license = licenses.bsd0;
-      maintainers = [ ];
-    };
-
-    nativeBuildInputs = [ pkgs.makeWrapper ];
-
-    postInstall = ''
-      wrapProgram $out/bin/nix-builder --prefix PATH : ${
-        lib.makeBinPath [
-          pkgs.git
-          pkgs.nix
-          pkgs.nixos-rebuild
-        ]
-      }
-    '';
-  };
-in
 {
   imports = [ ];
 
@@ -66,7 +20,7 @@ in
 
   config = lib.mkIf config.me.hydra.enable {
     environment.systemPackages = with pkgs; [
-      nix_builder
+      nix_builder.packages.x86_64-linux.default
       sqlite # For manually inspecting the database.
     ];
 
@@ -142,7 +96,7 @@ in
           IFS=$'\n\t'
           DIR="$( cd "$( dirname "''${BASH_SOURCE[0]}" )" && pwd )"
 
-          NIX_REMOTE='local?root=/.disk/root' RUST_BACKTRACE=1 RUST_LOG=nix_builder=DEBUG ${nix_builder}/bin/nix-builder build --config ${./files/nix_builder.toml} ${builtins.concatStringsSep " " build_flags}
+          NIX_REMOTE='local?root=/.disk/root' RUST_BACKTRACE=1 RUST_LOG=nix_builder=DEBUG ${nix_builder.packages.x86_64-linux.default}/bin/nix-builder build --config ${./files/nix_builder.toml} ${builtins.concatStringsSep " " build_flags}
         '';
         restartIfChanged = false;
         serviceConfig = {